Casing spear



CASING 5PMR Filed July 1929 M I LD Patented Oct; 7, s 1930 v UNITED STATES PATE'NTOFFICE- :DRIS THOMAS, OF WHIT'IIEB, CALIFORNIA CASING srnnn Application filed m a, 1929. Serial N nsen.

This invention relatesto fishingtoolso f the type disclosed in Patent Number 1,687

808, granted October 16,1928, to Ernest I r Tibbet and myself. In the present invention,

however, the preferred embodiment involves the useloii a longitudinally tapered portion or waiston the mandrel of the tool, carrying slips for engaging with the casing to be pulled. Tools of this type have been employed in which the slipsare maintained in an elevated position'on the waist by frangible means which may be broken after the spear has been inserted in the casing, operating to permit the slips to move relatively down 5 wardly on the mandrel toward the larger end of the tapered portion, thereby forcing the slips outwardly and anchoring themagainst thewall of thecasing. The general object of this invention is to' provide improved 29 means for mounting the slips on the mandrel and for enabling a relative rotation of the mandrel and slips, to enable the slips to be released at will; also to provide a tool of this class oi improved Construction, including v means for retaining the slips normally ln'a retracted position 1n whichthey are heldat an elevated position on thetapered waist of the mandrel. j j I In the preferred embodiment of the inven- 30 tion, the slips includeupwardly projecting tangsat their upper ends, which are retained by a ring or collar on the mandrel. The tool is constructed so that this collar can be passed up over the enlarged lower portion of the waist of the mandrel, and one of thefobjects of the invention is to' provid e a construction which will enable this to be. accomplished and,

at the same time, provide for effective guid-. ing of the upper tangs.oftheslips. v a A further object ofthe inventionis to provide means for connecting the lower ends of the slips in such a way that, if one of the slips engages the casing when the mandrel is V pulled upwardly, it will immediately communicate its relative downward movement to the other slips and insure that'all of the, slips will be at the same elevation on the waist at all times. In this way, I am sure that the f spear in operation will maintain itself centrally in the casing andthat itis not posslble pear'hereinafter;

theyare extended outwardly with-respect to jlligureais a e-horizontal cross-section taken 9 on the line tf i of F gure 1, upon an enlarged for any one of the slipsto become cocked or i thrown out ofproper alignment with the other slips. p j l i In the preferredembodiment of the inventionthe tapered waist of the mandrel is provided with circumferential cam faces engaging theslips, the presence ofwhich enables the, slips to be moved outwardly or inwardly with-respect to the axis of the mandrel, and one of the objects of the invention is to provide simple means in combination with the mandrel for limiting therotary movement of the slips with respect to the mandrel.

A further object of the invention is to improve the -general construction of toolssof this type and to provide a tool capable of being'used for pulling casings of difierent diameters. a V

Further objects of" the invention will apl The invention consists in'the novel parts and combination ofjpa-rts to be described hereinafter, all ofwhich contribute to pro- A preferredvembodiment of the invention is described in the iollowing specification, whilejthefbroad scope of the invention is pointedout in the appended claims.

.duce an eificient casing spear.

, i In the drawing s Figure l'isa vert cal section through a. casing spear embodymg my invent on.

1 beingbroken away and others shown in section-and partialsection. This view shows the slips in their lowe'redposition, in which the longitudinal axis-o fthe spear. V

F gure is a lhorlzontalcross-section onthe line l of F gure 1, upon an enlarged scale.

scale. a v Figure 5 is a horizontal cross-sectiom upon an enlarged; scaleptaken on the linear-5 0f i u al T a 1 V This' 7 r -v1ewsl1ows aportlon o fthe mandrel in elevation and: shows slips in their extreme ele- Figure 6 is a plan showing one of the segments of a liner which I prefer to employ for assisting in guiding the upper tangs of the slips.

Referring more particularly to the parts, 1 represents the mandrel of the casing spear, which is preferably constructed with an enlarged head 2 at its upper end having means such as a tapered threaded box 3 for attaching the same to the lower end of a tool strin Below the head 2 the mandrel isp'rovided with a tapered portion or waist 4 of general conical form, with a slight taper and having its larger end disposedfdownwardlytoward.

the lower end of the spear. I prefer to provide a neck 5 of reduced diameter at the upper end of the waist, and between it and'the head 2. This neck has circumferential cam faces 5"-(se'e The waist 4 of the spear is formed with a plurality of circumferential cam faces 6 (see Figure 4) the inner faces of theslips 6 are curved to fit against'these cam faces and against the cam faces 5 in such a way that by a relative rotation of the mandrel with respect to the slips, the slips can be moved outwardly or permitted to move inwardly with respect to the longitudinal axis of the spear;

The'upper ends of the slips are provided with upper tangs 7 of reduced widththat cooperate with the cam faces 5 (see' Figure 3), and these tangs are retained in a collar 8 which seat-s ona cylindrical-neck 9 of reduced diameter formed on the mandrel. If desired, a ball bearin'glO may be provided between thecollar and the neck- 9. I prefer to construct the tool so that this collar 8 can he slipped up on the tool from its I lower end. However, this necessitates a considerable inside diameter for this collar, which tends to give too much freedom of movement of the fangs 7 in the collar. In order to overcome this difficulty, I provide a liner 11 for the collar which preferably con 'sists of three sections, 11*, 11 and 11. These 'sec'tions'are just alike,' and one of them is illustrated removed from the'tool in Figure the inside diameter of the collar so that the ends 14 of the arcuate fingers meet together,

as illustratediiin Figure 3, thereby holding the liner 1'1 properly centered in the tool. The collar is alsoprovided with outwardly extending recesses 15 to, receive the'bodies of the segments or sectionsof the-liner (see Figure i Belowthe slips thespear is provided with means for normally holding all the slipsin an elevated position on the waist. For this purvided for holding this collar up but fo slips. In othenwords, where the against the casing by reason of the ion pose I prefer to provide a sliding collar 16 mounted to slide on an elongated neck 17 of reduced diameter at the lower end of the mandrel. Any suitable means may be prothis purpose I prefer to provide a coil spri the upper end of which is receivedin an annular chamber 19 formed wit iin the cellar, the upper end of the spring thrusting against a bottom ring 20 ofa ball-bearing 2L The lower end of the spring thrusts against the -bowl22 of the spear which may be attached in corresponding dove-tailnotchcs of the neck 17 by screw lo rm ed in the upper end of the collar 16. The tangs 23 are prevented from moving out of the dove-tail notches by means of an encircling retaining ring 25 (see Figure 1).

If desired, 1 may rely entirely upon the cam faces 6 for controlling the position of the slips'by relative rotary movei'nent V mandrel and slips, but I prefer to provide similar circumferential cam faces 46 on the mandreljust below the tapered waist por ion 4 and between it and the neck 17 (se ure 5). These cam faces 26 fit agaii s curved inner faces 27 of the lower and assist in forcing the slips out when the mandrel is rotated relativel" slips in a clock-wise direction,

down into a well with the mandrel in any rr i tive oriented position with relation to spear is being used on a relatively mg, the mandrel would be in an oriented pe sition holding the slips projected out as far as possible so that the slips may tench the wall of'the casing that is to be pulle order to anchor the spear to the cas' pulled the mandrel would be given an 1 wardpull or jar, which would set the sli nal taper of the waist.

. hen it is desired to release the casing spear, this can be done by rotat i t I drel in an anti-clockwise direction.

It will be evident that by reason of the cumferential cam faces 6 and 26, t. spear has a wide range of useful abling it to -be used for pulling casin s a considerable range in diameter. more, by reason of the interlocking conceit tion between the slips and the collar 16, it will be evident that the slips will always be he d at the same elevation on the waist 4;. T r; maintains the mandrel at all times centrallv in the casing that is to be pulled. The pres enceof the liner 11 insures elfective guiding of the uppertangs of the slips and the arcuate portion of the body of each segment of this liner prevents the tan'gs from having too great outward movement.

gIthas been found in practice that when on'weu workers employ tools. of this general type which include a longitudinally tapered waist on the mandrel, they may insert the casing spear with the slips in an extreme position which renders it impossible for the slips to function properly when they are to be set against the casing wall. This tool tendsto'overcome this objection and insures that the slips will always be held in their uppermost position. Hence, if the tool is run down into the casing in its expanded position, the slips cannot fail to bite against the casing when an upward pull is given to the mandrel; this will insure proper; releasing of the tool by relativerotation of the mandrel with respect to the slips.

While it is not essential, I prefer to provide means for limiting the relative rotary movement of the mandrel with respect to the slips. For this purpose I providea notch 28 in the upper edge of the collar 8 and I provide a downwardly projecting tongue 29 se- 'cured to the head of the mandrel and projecting down into this notch. The ends of this notch striking against the edges of the tongue 29 evidently will limit the relative rotary movement of the mandreland the slips.

The outer faces of theslips are provided with wickers or teeth for-engaging the inner face of the wall of a casing'such as the casing 30 '(see Fig. These wickers may be formed as illustrated withtwo zones 31 and S2 in which the teeth extend circumferentially, and I may provide between thesezones an intermediate zone 33 in which the teeth or wickers extend in a-longitudinal direction on the faceof the slip.

In using a tool of this liind having a longitudinal and circumferentially tapered Waist on the mandrel, I find inpractice thatwhen an upward pull has been exerted in which the slips 6 move downwardly relativelyon the tapered waist 4, there is tendency for them to sidle or shift laterally towardthereceding portions 6 -of the cam faces. This,"oi" course, is objectionable as it tends to"release theslips. I provide means on the waistof the mandrel which overcome this tendency.

For this purpose I provide the large-end of'the waist e adjacent the receding portion 6 of the cam faces with inclined shoulders 34 (see Fig. 1). If it should happen that'the slips 6 li'avemoved down relatively on the waist of the mandrel-and they tendfto sidle' toward the recedingportion of the cam, they will engage these 1nclined faces 34, which I faces will exert a lateralthrust uponthe slips to prevent this lateral shifting ersi'dlin'ig movement. In this waytheslips a're m'ade;

to"stand up underthe pressure and cannot shift around on the mandrel insuch a way as to loosen themselves. This tendency of the slips to sidle around on the mandrelis not objectionable if the slips have not slid down considerably, because if they-are being pressed by the mandrel well up on the tapered practice of the invention, nor in the claims,

to the particular embodiment set forth.

VJhat I claim is:

1. In a casing spear, the combination of. a mandrel having a head at its upper end for attaching the same to a tool string,said mandrel having atapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, yielding means for holding the slips in an elevated position on thewaist, said waist having circumferential cam faces'tomove the slips'in or out when the mandrel is rotated relatively to the slips.

2. Ian. casm'g'spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, and having tangs at their upper r ends, a collar distinct from the mandrel mounted on the man'drel and havingmeans for retainingthe tangs'against outward and lateral movement in any operating position of the same, yielding means for holding the slips ina'n elevated position on the waist. said waist ha ving circumferential cam faces operating to permit the slips to move inor out when the mandrel is rotatedrelatively to the slips 'whilethey' are engaging the casing.

3. Ina casingspear,the combination-of'a upper ends, means ='separate from "the mandrel mounted 'on-the mandrel forengaging said tangs-on their outer faces and side edges to retain the slips on i the mandrel, said slips having tang's at their lower ends, means iso mounted to 'slide on the nian'drel below-,the 4 saidwaist for engaging the lower tan'gs to retain 5 the slips at tllell lower ends, anda spring engaging said means and normally holding the same and the slips in an elevated position, said waist, having circumferential cam faces operating to release the slips and permit the same to move inwardly toward the axis of the mandrel when the mandrel is rotated relatively to the slips when the slips are set on the inside of a casing.

4. Ina casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, a collar mounted to slide on the mandrel below the slips, said collar and said slips having means for enabling the slips to interlock with the collar by radial movement of the slips toward the mandrel, said collar having means for preventing outward movement of the lower ends of the slips after interlocking with the collar, and a spring normally holding the collar in an elevated position, said waist having circumferential cam faces for engaging the inner faces of the slips and operating to move the slips in or out when a relative rotation of the mandrel occurs with respect to the slips.

5. In a casing spear, the combination of a mandrel having a head at its 111 per end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, and having tangs at their lower ends, a collar mounted to slide on the mandrel below the waist, said-tangs being of substantially dove-tail form and said, collar having slots receiving the tangs and interlocking with the same when the slips are moved radially inwardly toward the axis of the mandrel, and a spring on the mandrel. for normally holding the collar and the slips elevated.

6. In a casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for en gaging a casing, and having tangs at their lower ends, a'collar mounted to slide on the mandrel below the waist, said tangs being of substantially dove-tail form and said collar havingslots receiving the tangs and interlocking with the same when the slips are moved radially inwardly toward the axis of theimandrel, and a spring on the mandrel for normally holding the collar and the slips elevated, said slips having tangs at their upper ends and a collar on the mandrel above the slips for retaining the last named tangs.

7 ..In a casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said man drel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, and having tangs at their upper ends, a collar on the mandrel for engaging the outer faces and side edges of the tangs for guiding the tangs longitudinally on the mandrel, and for retaining the tangs, yielding means for holding the slips in an elevated position on the waist, said waist having circumferential cam faces 0perating to permit the slips to move in or out when the mandrel is rotated relatively to the slips while they are engaging the casing, and means for limiting the relative rotary movement of the mandrel with respect to the slips.

8. In a casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for en gaging a casing, and having tangs at their upper ends, a collar capable of being passed up the mandrel from below and past the said waist to a point opposite said tangs having means for maintaining the tangs in longitudinal alignment with the mandrel and for limiting the outward movement of said tangs, a lower collar mounted to slide on the mandrel below the waist and having means for retaining the lower ends of the slips, and a spring on the mandrel for normally holding the last named collar and the slips in an elevated posit-ion.

9. In a casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, and having tangs at their upper ends, a collar capable of being passed up themandrel from below and past the said waist to apoint opposite said tangs for re taining said tangs, a lower collar mounted to slide on the mandrel below the waist and having means for retaining the lower ends of the slips, and a spring on the mandrel for normally holding the last named collar and the slips in an elevated position, and a segmental liner for the first named collar capable of beingput in place after the upper collar has been slid upwardly over the mandrel to a point near the location of the said tangs.

10. In a casing spear, the combination of a mandrel having a head at its upper end for attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality ofslips mounted on the tapered waist for engaging a casing, and having a plurality of tangs at their upper ends projecting upwardly, a collar capable of being slipped upwardly over the lower portion of the mandrel to a point opposite the tangs for retaining the tangs, a liner for thesaid collar including a'plurality of segmentscorresponding to the tangs and guiding the tangs, and

for normally position.

means mounted on the mandrel below the,

waist for retaining the lower ends of the slips. 11. In a casing spear, the combination of a mandrel having a head at its upper end for.

attaching the same to a tool string, said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of-slips mounted on the tapered waist for engaging a casing, and a plurality oftangs at their upper ends projecting upwardly, a collar capable of being slipped upwardly over the lower portion of the mandrel to a point opposite the tangs for retaining the tangs, a liner for the said collar including a plurality of segments corresponding to the tangsand engaging the outer faces and side edges of casing, and having a plurality of tangsat their upper ends projecting upwardly, a collar capable of being slipped upwardly over the lower port-ion of themandrel to a point opposite the tangs for retaining the tangs, a

liner for the said collarincluding a plurality of segments corresponding to the tangs and guiding. the tangs, and means mounted on the mandrel below the waist for retaining the lower ends of the slips, and a spring associated with the last named means for nor mally holding the slips in an elevated position, said mandrel having circumferential cam faces corresponding to the slips for moving the slips in or out when the mandrel has a relative rotation with respect to the slips.

13. In a casing spear, the combination of a mandrel having a head at its upper end for attaching the sameto a tool string, and'hav ing a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging the casing, said waist having circumferential cam faces to cooperate with the slips to en able the same to move in or out when the mandrel is rotated relatively to the slips, and means on the mandrel operating to engage the lower ends of the slips and exert a lateral force upon the same to prevent the slips from sidling laterally on the cam faces toward the depressed portions thereof.

14;. .In a casingspear, the combination of v i v a mandrel having a head at-its upper end for attaching the same to atool string, and having a tapered waist withits larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging the casing, said waist having circumferential cam faces to cooperate with the slipsto enablethe same to move in or out when the mandrel is rotated relatively to the slips, said waist having shoulders located toward the large end of the waist and adjacent the receding portions of the cam faces, and disposed in an inclined direction, said shoulders operating to engage' the lower ends of the slips and exert a lateral force upon the same to prevent the slips from sidling laterally on thecam-f aces toward the depressed portions thereof. v

.15. Ina casing spear, the combination of a mandrel having a head atits upper end for attaching the same to a tool string,said mandrel having a tapered waist with its larger end disposed downwardly, a plurality of slips mounted on the tapered waist for engaging a casing, yielding means for holdmg the slips in an elevated position on the waist,said waist having circumferential cam, faces to move theslips'm or out when the l mandrel is rotated relatively to the slips, and

having shoulders located toward the large end of the waist and adjacent the cam receding portions of the cam faces, and disposed in an inclined direction and operating to en gage the lower ends of the slips and force the same laterally on the faces of the cams and toward the projecting portions of the cam faces.

Signed at Los Angeles, Calif, this 27th day of June, 1929. v

j IDRIS THOMAS. 

